Study: Legal wolf culling increases intolerance and illegal killing

May 12, 2016

Allowing the culling or hunting of wolves is substantially more likely to increase poaching, or illegal killing, than to reduce it, suggests new research by UW-Madison Associate Professor of Environmental Studies Adrian Treves and Guillaume Chapron of the Swedish University of Agricultural Sciences.

The researchers studied changes in wolf policies in Wisconsin and Michigan between 1995 and 2012, when the federal status of wolves changed 12 times and culling was alternately allowed and banned in the two states. The co-authors found that the repeated policy signal to allow state culling triggered slowdowns in wolf population growth, most likely caused by poaching, they infer. The findings were published May 11 in the journal Proceedings of the Royal Society B.

The study is the first quantitative evaluation of a dominant theory in wildlife conservation: that liberalizing culling will reduce poaching and improve the population status of an endangered carnivore. Rather, the researchers conclude, granting local authorities management flexibility for endangered species to address illegal behavior may instead promote such behavior.

“Each time the state had the authority to cull wolves, we found a decrease in the population growth of wolves,” Treves told the Madison-based Isthmus.

The co-authors reason that when the government kills a protected species, the perceived value of each individual of that species may decline. Liberalizing wolf culling may have sent a negative message about the value of wolves or the acceptability of poaching, they suggest.

“If the government lowers the value of wolves with high quotas, low fees and a disrespect for the species, poachers may kill more wolves than they have in the past,” the co-authors said in a fact sheet. “Moreover, if hunting is designed in a way that facilitates poaching, the government signal will be loud and clear: We are not enforcing anti-poaching laws, and we do not value wolves.”